Oscillating transmission devices for rotatable sprinklers have been known in the prior art for use in irrigation. Patents setting forth a background for this invention are: U.S. Pat. Nos. 3,107,056; 3,645,451; 3,713,584; 3,724,757; 3,854,664; 4,272,024; 4,353,507; 4,568,024; and 4,625,914.